To follow along in this article, you should have the following items:

Before we begin, we need to briefly discuss notation used throughout the rest of the article. Most of the directories mentioned in this tutorial are relative to the root directory where you unzipped the Expresso-complete installation. We will denote this root directory as ${EXPRESSO_INSTALL_DIR}. So for clarification, let's say, for example, that you've unzipped Expresso into the C:/expresso directory. If you see the notation ${EXPRESSO_INSTALL_DIR}/webapps/ROOT/WEB-INF/lib, then given the base directory, the full path would be: C:/expresso/webapps/ROOT/WEB-INF/lib

So let's get started! Launch IDEA. If you do not get prompted with the new project dialog, go to File -> New Project. For the project name, enter "Expresso". Select the JDK to use with the project. If you do not have a JDK configured, click on the ellipsis (...). If the list for "Select JDK" is blank, click on the Configure button and select the root directory where you have your Java Development Kit installed. Now for the Compiler Output Path, select ${EXPRESSO_INSTALL_DIR}/webapps/ROOT/WEB-INF/classes. There is a screenshot included below that shows what the dialog might look like when everything is entered. Now click Next.

For the project path dialog, enter ${EXPRESSO_INSTALL_DIR}/webapps/ROOT/WEB-INF/src (Remember to substitute ${EXPRESSO_INSTALL_DIR} with the directory you installed Expresso-complete into.)

You should now be at the "Source Path" screen. Click on Add Path. Now locate the directory ${EXPRESSO_INSTALL_DIR}/webapps/ROOT/WEB-INF/src and select that as your source path. Aside from a different directory, your source path dialog will look similar to that listed below. Once you have selected this, click on the Next button.

Now for setting up the classpath for an Expresso project. There are several items that have to be added here:

Once the project is created, click on the "Project" tab in the upper left hand corner of the screen. It should look similar to the picture that is below.

Expresso relies of XML Document Type Definitions to be copied into the output path along with the source files. Unfortunately, IDEA doesn't copy DTD's to the output directory by default. To set this up, we select the menu item: File -> Project Properties. Now click on the Compiler button. Near the bottom of the page is a box titled Resource Patterns. Change this entry to:

		.+\.(properties|xml|html|dtd);.+\.(gif|png|jpeg|jpg)

Ok, it is time to put our procedure to the test! From the IDE menu select Build -> Rebuild Project. You should see the IDE compile approximately 500 files. Although you will see several "Deprecation Warnings", there should be no actual compilation errors. If there are errors, you need to double-check your setup procedure. If you cannot find your error, you are encouraged to post to the JCorporate forums or OpenSource mailing list for assistance.

Now it is time for a little side trip. Locate the file ${EXPRESSO_INSTALL_DIR}/conf/server.xml and open it for editing. Locate inside the following lines of code:

				<!-- Tomcat Root Context -->
				<!--
				<Context path="" docBase="ROOT" debug="0"/>
				-->

	 <Context path="/myappname" docBase="myappname" debug="0"/>

There are a couple of ways to set up debugging here the IDEA can support. You can either attach to a Tomcat server remotely, or you can launch the entire Tomcat server within the IDE. Because the latter is a little bit simpler to set up, we will cover this method more extensively.

First we have to do a small tweak. For some reason, most likely Classloader related, log4j does not work if in the WEB-INf/lib directory. Instead, copy the log4j jar file from ${EXPRESSO_INSTALL_DIR}/webapps/ROOT/WEB-INF/lib to ${EXPRESSO_INSTALL_DIR}/common/lib directory.

In the IDE menu click Run -> Debug. The Debug settings dialog pops up. Click on the "Web App" tab and press the "+" button. For a name, enter "Tomcat."

For the Web Application box, click the Configure Button. Click the "Enable Web Application support" button. Now click the Add Button. For the Name, enter ROOT; for the Path to Document Root, enter ${EXPRESSO_INSTALL_DIR}/webapps/ROOT. You can click on the "Validate JSP" pages if you wish. For Application Server, keep the default of "Tomcat 4.0.x Server." Check the box: "Launch server before debugger attaches" box.

For the Runtime configuration enter the following parameters:

<target name="debug"
                depends="compile"
                description="development debug startup, occupies current shell; terminate with control-C or gracefully via Tomcat shutdown script" >
        <mkdir dir="${basedir}/logs"/>

        <java classname="org.apache.catalina.startup.Bootstrap"
                failonerror="true"
                fork="true"
                dir="${local.tomcat.home}"
                >
                <classpath refid="tomcat.classpathset"/>
    <sysproperty key="catalina.home" value="${local.tomcat.home}" />
    <sysproperty key="catalina.base" value="${local.tomcat.home}" />

    <sysproperty key="java.compiler" value="NONE" />
                <jvmarg value="-Xrunjdwp:transport=dt_shmem,server=y,suspend=n,address=5005" />
                <jvmarg value="-Xdebug" />
                <jvmarg value="-Xnoagent" />

                <jvmarg value="-Xms128m" />
                <jvmarg value="-Xmx250m" />

                <arg value="start" />
        </java>
</target>

%ANT_HOME%\bin\ant debug